The Impact of Pulsed Electric Field on the Extraction of Bioactive Compounds from Beetroot

Abstract

Beetroot is a root vegetable rich in different bioactive components, such as vitamins, minerals, phenolics, carotenoids, nitrate, ascorbic acids, and betalains, that can have a positive effect on human health. The aim of this work was to study the influence of the pulsed electric field (PEF) at different electric field strengths (4.38 and 6.25 kV/cm), pulse number 10–30, and energy input 0–12.5 kJ/kg as a pretreatment method on the extraction of betalains from beetroot. The obtained results showed that the application of PEF pre-treatment significantly (p < 0.05) influenced the efficiency of extraction of bioactive compounds from beetroot. The highest increase in the content of betalain compounds in the red beet’s extract (betanin by 329%, vulgaxanthin by 244%, compared to the control sample), was noted for 20 pulses of electric field at 4.38 kV/cm of strength. Treatment of the plant material with a PEF also resulted in an increase in the electrical conductivity compared to the non-treated sample due to the increase in cell membrane permeability, which was associated with leakage of substances able to conduct electricity, including mineral salts, into the intercellular space.

Safety, Quality, and Processing of Fruits and Vegetables

“…Therefore, this study confirms that, when used as a processing aid for potato, PEF does not result in detrimental effects on the properties of potato starch [6]. PEF has been shown to be effective in the extraction of bioactive compounds (mainly betalains) from beetroot, increasing the extraction yield [7]. The greatest increase in the content of betalain compounds in the red beet extract was noted when an electric field at 4.38 kV/cm was applied [7].…”

“…PEF has been shown to be effective in the extraction of bioactive compounds (mainly betalains) from beetroot, increasing the extraction yield [7]. The greatest increase in the content of betalain compounds in the red beet extract was noted when an electric field at 4.38 kV/cm was applied [7]. The increase in the extraction rate of polyphenols from olive leaves was also observed by using high-voltage electrical discharges (HVED) as a green technology [8].…”

Red Beetroot. A Potential Source of Natural Additives for the Meat Industry

“…Despite the large number of compounds referred to by the term betalains, the betacyanins that are found in the highest concentration in beetroot are, in decreasing order, betanin, isobetanin, neobetanin, and probetanin ( Figure 2). In the case of the betaxanthins present in beetroot, also in descending order, they are vulgaxanthin I, vulgaxanthin II, indicaxanthin, miraxanthin, and portulaxanthin ( Figure 3) [3,5,24,31]. Despite this, different studies have observed a large number of betalains in beetroot.…”

Beetroot, A Remarkable Vegetable: Its Nitrate and Phytochemical Contents Can be Adjusted in Novel Formulations to Benefit Health and Support Cardiovascular Disease Therapies

“…Red beetroot ( Beta vulgaris L. species) is a source of bioactive compounds, including dietary NO 3 − , betanin, antioxidant substances, and phenolic compounds (PCs), as well as a source of dietary fiber, minerals (potassium, sodium, iron, copper, magnesium, calcium, phosphorus, and zinc) and vitamins (retinol, ascorbic acid, and B-complex) [ 3 , 10 ]. However, dietary NO 3 − supplementation from beetroot requires smart formulations, to provide convenient serving portions while also containing effective concentrations of NO 3 − and bioactive compounds as a feasible alternative to the consumption of whole in natura vegetables.…”